1. Field
Example embodiments relate to equipment for electrically testing semiconductor devices. Also, example embodiments relate to handlers, which are automatic test robots, that perform loading, grouping, and unloading operations on one or more devices under test (DUTs).
2. Description of Related Art
Surface mount devices (SMDs), such as, small outline package (SOP), quad flat package (QFP), ball grid array (BGA), and chip size package (CSP) semiconductor packages, have a problem in that their leads or solder balls are easily damaged even with small external impacts after the SMDs are completely assembled. To prevent this problem, SMDs use protector-carriers that are called trays.
When semiconductor devices are electrically tested, a handler, which is an automatic testing robot, is physically and electrically connected to a tester. The handler loads the semiconductor devices thereinto, electrically connects the semiconductor devices to the tester to perform electrical testing operations on the semiconductor devices, and classifies the semiconductor devices according to results of the electrical tests. To convey the semiconductor devices, the handler uses trays as carriers. A plurality of semiconductor devices are horizontally loaded on the trays having matrix type pockets. The trays are roughly classified into user trays, used to convey and hold the semiconductor devices, and test trays, used to connect the semiconductor devices to a tester within the handler. The test trays are used as intermediate media to connect the semiconductor devices to a tester while the semiconductor devices are in the handler.
FIG. 1 is a perspective view of a conventional handler 10 for testing semiconductor devices. FIG. 2 is a front view of the conventional handler 10 of FIG. 1, viewed from the direction A.
Referring to FIGS. 1 and 2, the conventional handler 10 has a front top door 12 on the top part of the front side. The front top door 12 has a transparent or substantially transparent window 22 through which the inside of the conventional handler 10 can be checked with human eyes. A first handle 14 is on the front top door 12. When a problem occurs within the conventional handler 10, an operator opens the front top door 12 by means of the first handle 14 in order to check the inside of the conventional handler 10. A control panel 26 used to control the conventional handler 10 is on the left side of the front top door 12. The operator controls the operation of the conventional handler 10 by using the control panel 26. An alarm lamp 20 is on the front top door 12 so that the operator can easily detect problems occurring within the conventional handler 10.
A stocker portion is under the front top door 12 and covered by a batch-type stocker cover 16. A gauze window 24 is on the batch-type stocker cover 16 and is made of metal. The stocker portion serves as a passage through which semiconductor devices enter to be electrically tested and/or semiconductor devices that have completed the electrical tests come out. The input and output of the semiconductor devices are performed with the batch-type stocker cover 16 opened by pulling a second handle 18 forward as indicated by thinner arrow D.
FIG. 3 is a perspective view of a plurality of stockers 32 that are included in the stocker portion of FIG. 1. Referring to FIG. 3, the stockers 32 are classified into stockers 32A, used when semiconductor devices seated on user trays 101 are put in to perform electrical tests, and stockers 32B, used to classify test-completed semiconductor devices according to the test results and to arrange them accordingly. The user trays 101 are conveyed by a tray conveyance robot 30 that repeats X-axis and Y-axis movements over the stockers 32A and 32B.
Technology relevant to the conventional handler 10 used to electrically test semiconductor devices has been published in U.S. Pat. No. 6,346,682, entitled “Rambus Handler,” patented on Feb. 12, 2002, the entire contents of which are incorporated herein by reference.
However, the conventional handler 10 needs to be improved in a number of respects. It is very burdensome to open the heavy steel batch-type stocker cover 16 using the second handle 18 in order to put semiconductor devices to be electrically tested into the conventional handler 10 or to take semiconductor devices having completed electrical tests out of the conventional handler 10. In general, a single operator performs an electrical test on semiconductor devices while managing at least ten handlers. Hence, the burdensome opening and closing of the heavy batch-type stocker cover 16 for injection and ejection of semiconductor devices degrades the efficiency of production.
Also, the batch-type stocker cover 16 is easily and frequently out of order because of a structural problem of the batch-type stocker cover 16. In a process of frequently opening and closing the batch-type stocker cover 16 made of steel, the handle of the batch-type stocker cover 16 frequently breaks. This increases the time required for maintenance, consequently degrading the operation rate of the conventional handler 10 and degrading the productivity of handlers. When the batch-type stocker cover 16 is more severely broken and separated from the conventional handler 10 onto the floor, there is a safety concern that an operator may get hurt.
Furthermore, the gauze window 24 of the batch-type stocker cover 16 prevents an operator from easily checking the condition of the inside of the stocker portion, so the batch-type stocker cover 16 needs to be frequently opened. Since the tray conveyance robot 30 moves within the stocker portion, when an operator puts his or her hand into the stocker portion, there is a safety concern that the operator may get hurt.